【简答题】• Suppose that one day you are going to do business with a westerner. You'd like to have dinner with him and show him the beautiful sight of your city. But in the westerner's perspective, it has nothi...
【单选题】Suppose that for the past two months, you have studied economics one hour a day. You now decide to study economics two hours a day. For the past two months, ( ).
A.
your marginal cost of studying economics for an hour must have exceeded its marginal benefit
B.
the marginal cost of studying economics must have fallen
C.
your marginal benefit from studying economics an hour must have been greater than its marginal cost
D.
the opportunity cost of studying economics must have risen.